Means for sealing adjustable pivots for rotatable bodies



Nov. 4, 1-947. N. A. H. \HLSSON ET AL 2,430,135

MEANS FOR SEALING ADJUSTABLE PIVOTS FOR ROTATABLE BODIES Filed June 2, 1945' Patented Nov. 4, 1947 UNITED- STATES PATENT OFFICE Aktiebolaget C. E. J ohansson, Eskilstuna, Sweden, a company of Sweden Application June 2, 1945, Serial No. 597,352 In Sweden May 31, 1944 Claims. (Cl. 30862) The present invention relates to means for sealing adjustable pivots for rotatable bodies, such as the pivots of rotatable measuring elements of measuring tools, for instance, thread gauging rolls 'of limit thread snap gauges. In such tools the stud or pivot is provided with an eccentric portion, and is rotatably attached to the frame of the tool for the purpose of permitting adjustment or the pivot and thus of the measuring element pivoted thereon. For this purpose the pivot is provided with a screwdriver slot or with some similar means which may be engaged by a tool serving to turn the pivot. In order to prevent unauthorized adjustment of such gauging rolls or similar rotatable measuring elements or bodies, the eccentric pivots must be sealed after having been adjusted in proper position. Since the body or measuring element must be free to rotate on the pivot when the measuring tool is used, however, it is not possible in this case to employ the ordinary method of sealing which is practised for sealing such adjustment screws, for example, that are screwed into a screw-threaded bore, and which consists in forcing a seal, for instance of lead or other comparatively soft material, into the bore outside the adjustment screw, since in the present case such aseal would prevent the measuring element from turning.

It is the purpose of the present invention to provide a sealing means which renders it possible efiectively to seal adjustable pivots for rotatable bodies, such as adjustable gauging rolls or similar measuring elements which must be free to rotate about their pivots. With this purpose in view, an important feature of the present invention consists in the eccentric pivot of the rotatable body or measuring element being provided with a recess or pocket at its free end, the said screwdriver slot or tool engaging means being provided in the bottom of said pocket, and a seal, for instance of lead or other comparatively soft material, being inserted in said pocket to cover said screwdriver slot or tool engaging means at the bottom thereof. In this manner it is impossible to get at the screwdriver slot or the like and thus to turn the pivot without first removing the seal.

The accompanying drawing illustrates by way of example two constructional forms of the invention. Fig. 1 shows an axial section of a sealing means according to the invention for the pivot of a rotatable gauging roll, and Fig. 2 shows the pivot viewed from above as seen in Fig. 1. Fig. 3 shows a slightly modified construction in which the pocket is formed of 'a separate washer,

and Fig. 4 shows such washer placed on the pivot before it is bent up around the end of the latter.

In both constructional forms illustrated in the drawing, l denotes the gauging roll whichin this case is assumed to be a, thread gauging roll of a limit thread snap gauge, and 2 denotes a portion of the frame or the gauge. The gauging roll I is freely rotatable on a stud or pivot 3 which is adjustably securedto the frame 2 by said pivot 3 being provided at one end with a pin or projection 4 having a smaller diameter and located 'e'ccentri'cally relatively to the body of the pivot 3. Said pin is inserted in a through bore 5 in the frame land may be secured to the latter by means of a set screw 8 which is screwed from the other Side of the name into a screwthreaded bore 1 in the pin 4. The said set screw 6 is preferably sealed in the ordinary manner by means of a seal 8 of lead or the like so that it cannot be tampered with. 7

The eccentric pivot 3 is provided at its outside end, that is, its upper "end as viewed in Figs. 1 and 3, with a head 9 having a somewhat larger diameter than the remainder of the pivot, whereby the gauging roll I is prevented from sliding off the pivot. According tothe invention, the said head is provided with a pocket H] the bottom of which is provided with -a-slot H serving to receive a screwdriver for turning the pivot The pocket Ill also serves toreceive a seal f2. The pocket It) is bordered'by a surrounding projecting edge It. In the constructional form illustrated in Figs. 1 and 2 the *said edge is made integral With the head '9, the pocket It thus forming a shallow bore in the upper face of said head. In the construction illustrated in Figs. 3 and 4, on the other hand, the edge i3 is formed of a separate washer M which is placed on the pivot 3, as shown in Fi 4, and is then bent up around the head 9 of said pivot, the washer being so dimensioned that it projects slightly above the upper face of the head and thus forms the desired pocket for receiving the seal [2.

It will be understood that in either case the screwdriver slot ll must not extend laterally through the projecting edge l3 since in such case it might be possible by means of a pointed tool to pick the seal l2 out of the pocket It). In order to fulfill this requirement the slot I! in the construction illustrated in Figs, 1 and 2, is formed by a hole I5 being first drilled crosswise through the head 9 below the projecting edge I3, and the slot being then formed between said hole and the bottom of the pocket inside the edge I3. The said 3 slot together with the hole l5 thus form the slot for receiving the screwdriver.

When it is desired to adjust the gauging roll I the set screw 6 is first loosened slightly so that it is possible to turn the pivot 3 by means of a screwdriver inserted in the slot H. Since the pivot 3 is eccentric relatively to the pin 4 around which the pivot 3 turns, the desired displacement of the gauging roll I parallel to itself is effected in this manner. The desired adjustment having been effected, the set screw 6 is again tightened, and finally, the said screw is sealed in the ordinary manner by means of the seal 8, and the eccentrio pivot 3 is sealed by mean's'ofthe seal |2."Il1 this Way it is impossible to get at the slot I l and thus to turn the pivot 3 withoutfirst removing the seal 1 2. In spite of the said seal, howeven-the gauging roll I is still free to turn on the pivot 3,

The constructional forms above described and illustrated in the drawing are only to be regarded as examples, and it will be-understood-that' the invention: 'is capable of :variouspappli'cationsj and modifications within the scope of the following claims i. V i We claim: L 'I'he combination 'with a frame, a stud-rotatablyattachcd atonend to said framcand having atits-otherfreeend means such as a screwdriver slotadapted to be engagedby-a tool for adjustting said stud relatively to said ;frame,and a body rotatably journalled on said StudaS a pivot, "of means for-sealing saidjstud in adjusted-position relatively to said frame, -said sealing means consisting of a-pocket at the'yfree end of-said stud, the said tool engagingmeans being provided'in the bottom of said Docket, and' a seal inserted in saidpocket'to coversaidtoo} engaging means at the bottom thereof; I a -2. The combination with a f-rame,'a studrotatably attached at one endto'said frame and having at its other free end means suchas a screwdriver slot'adapted to be engaged by a tool for adjusting said stud relatively' to said frame, said stud having a portion eccentric t0 the axis of rotation of the stud in said frameand a body rotatably journalled on said eccentricportionof said stud as a pivot,--of means for sealing'saidstudin adjusted position relatively-tq-said frame, saidsealing means'consisting of a pocket at the free end of said-stud, the said tool engaging-means being provided in the bottom of said pocket, and a seal inserted in said pocket to cover said tool engaging means at the bottom thereof. I

3. The combination with a-frame, a stud rotatably attached at one end tosaid frame and having at its other free end means such as a screwdriver slot adapted to be engaged by a tool for adlusting said stud relatively to said frame, and a body rotatably journalled on said stud as a, pivot, of means for sealing said stud in adjusted position relatively to said frame, said sealing means consisting of a pocket at the free end of said stud, said pocket being formed of a washer placed on the pivot and pressed up around the end thereof to form a bordering edge projecting beyond the end. face of the pivot which forms the bottom of said pocket, the said tool engaging means being provided in the bottom of said pocket, and a seal inserted in said pocket to cover said tool engaging means'at the bottom thereof.

4. 'The combination with a frame, a stud rotatably attached-at one end to said frame and having at its other free end a slot adapted to be engaged by a screwdriver for adjusting said stud relatively to said frame, and a body rotatably journalled on said stud as a pivot, of means for sealing said stud in adjusted position relatively to said frame; said'sealing means consisting of a pocket at'the free end of 'said'stud, the said screwdriver slot extending from the bottom of said pocket to a transverse hole in the stud inside said pocket, and a seal'inserted-in' said pocket to cover said screwdriver slot at the bottom thereof. T 5. In ameasuring tool of the character described, the combination of a frame, at .least'one stud rotatably attached at one end to saidframe and having at its other free end a slot adapted to be engaged by a screwdriver for turning and adjusting said stud relatively to said frame, said stud having a portion eccentric to the axis of rotation of the stud in said frame, a gauging roll rotatably journalled on said eccentric portion of said stud as a pivot, means, for sealing said stud in adjusted position relatively to saidframe, said sealing means consisting of a pocket at the free end of said stud, the said screwdriver slot being provided in the bottom of said pocket, and a seal inserted in said pocket to cover said screwdriver slotat the bottom thereof.

NILS AXEL HUGO NILSSON. ADOLF HAMPUS GABRIEL DAHLBOM;

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

